Crossref journal-article
Wiley
Molecular Microbiology (311)
Abstract

SummaryThe H‐NS nucleoid structuring protein has been shown previously to play a negative role in controlling virulence gene expression in Shigella flexneri by repressing transcription of the virF and virB regulatory genes and the VirF‐dependent icsA structural gene under non‐permissive growth conditions. Here, we show that H‐NS also acts at the promoters of the VirB‐dependent structural genes in the regulatory cascade. H‐NS protein binds to the promoter regions in vivo and in vitro. The promoters were shown physically and by in silico analysis to contain regions of DNA curvature, a feature of H‐NS binding sites. H‐NS binding sites were determined by DNase I footprinting at the icsB and the virA promoters. The locations of these sites were consistent with a role for H‐NS as a transcription repressor. The VirB‐dependent structural gene promoters were found to respond directly to the H‐NS repressor, revealing a level of control that is additional to that exerted by the H‐NS‐dependent virB activator gene. Moreover, the promoters were sensitive to the level of VirB protein in the cell, requiring a threshold level of VirB to be reached before becoming active. A model is discussed in which the levels of expression of the structural genes reflect the outcome of competition between the countervailing regulatory activities of the H‐NS and VirB proteins.

Bibliography

Beloin, C., & Dorman, C. J. (2003). An extended role for the nucleoid structuring protein H‐NS in the virulence gene regulatory cascade of Shigella flexneri. Molecular Microbiology, 47(3), 825–838. Portico.

Authors 2
  1. Christophe Beloin (first)
  2. Charles J. Dorman (additional)
References 53 Referenced 89
  1. 10.1111/j.1365-2958.1989.tb00210.x
  2. 10.1046/j.1365-2958.1997.3151679.x
  3. 10.1074/jbc.M111429200
  4. 10.1046/j.1365-2958.1999.01176.x
  5. 10.1016/0378-1119(77)90000-2
  6. 10.1002/j.1460-2075.1989.tb08615.x
  7. 10.1016/0003-2697(76)90527-3
  8. 10.1016/0022-2836(76)90119-4
  9. 10.1093/nar/28.18.3504
  10. 10.1128/IAI.69.1.15-23.2001
  11. 10.1046/j.1365-2958.2000.02120.x
  12. 10.1111/j.1365-2958.1993.tb01634.x
  13. 10.1046/j.1365-2958.1998.00902.x
  14. 10.1016/S0966-842X(99)01455-9
  15. 10.1078/1438-4221-00105
  16. 10.1093/emboj/17.23.7033
  17. 10.1046/j.1365-2958.2001.02646.x
  18. Free A.(1995)H‐NS and the Regulation of Transcription inEscherichia coli.PhD Thesis University of Dublin Trinity College.
  19. 10.1093/nar/22.24.5497
  20. 10.1128/jb.177.14.4121-4130.1995
  21. 10.1016/0092-8674(88)90470-9
  22. 10.1046/j.1365-2958.2001.02358.x
  23. 10.1111/j.1365-2958.1992.tb01385.x
  24. 10.1016/S0021-9258(17)37411-2 / J Biol Chem / Interactions of the nucleoid‐associated DNA‐binding protein H‐NS with the regulatory region of the osmotically controlled proU operon in E. coli by Lucht J.M. (1994)
  25. 10.1073/pnas.85.8.2820
  26. 10.1128/iai.43.1.195-201.1984 / Infect Immun / Temperature‐dependent expression of virulence genes in Shigella flexneri by Maurelli A.T. (1984)
  27. 10.1128/iai.49.1.164-171.1985
  28. 10.1038/nrmicro1088
  29. 10.1128/jb.177.17.5062-5069.1995
  30. 10.1128/JB.180.14.3522-3528.1998
  31. 10.1016/0092-8674(92)90354-F
  32. 10.1098/rstb.2000.0599
  33. Porter M.E.(1998)The Regulation of Virulence Gene Expression inShigella flexneri.PhD Thesis University of Dublin Trinity College.
  34. 10.1128/jb.176.13.4187-4191.1994
  35. 10.1128/jb.179.21.6537-6550.1997
  36. 10.1007/s004380050550
  37. 10.1111/j.1574-6968.1997.tb10237.x
  38. 10.1128/JB.184.2.531-539.2002
  39. 10.1016/S0923-2508(97)83619-4
  40. 10.1128/jb.170.6.2480-2484.1988
  41. 10.1128/jb.175.8.2334-2346.1993
  42. 10.1046/j.1365-2958.2000.01917.x
  43. 10.1111/j.1365-2958.1991.tb00762.x
  44. 10.1128/jb.175.19.6142-6149.1993
  45. 10.1128/jb.177.4.1094-1097.1995
  46. 10.1002/j.1460-2075.1994.tb06256.x
  47. 10.1006/jmbi.1996.0566
  48. 10.1006/jmbi.1997.1381
  49. 10.1080/07391102.1999.10508294
  50. 10.1111/j.1574-6968.1997.tb12724.x
  51. 10.1128/jb.178.15.4335-4343.1996 / J Bacteriol / Probing the structure, function, and interactions of the Escherichia coli H‐NS and StpA proteins by using dominant negative derivatives by Williams R.M. (1996)
  52. 10.1093/oxfordjournals.jbchem.a123216
  53. 10.1111/j.1365-2958.1994.tb01012.x
Dates
Type When
Created 22 years, 5 months ago (March 12, 2003, 6:47 a.m.)
Deposited 1 year, 10 months ago (Oct. 14, 2023, 3:59 p.m.)
Indexed 3 months ago (June 4, 2025, 6:29 a.m.)
Issued 22 years, 7 months ago (Jan. 15, 2003)
Published 22 years, 7 months ago (Jan. 15, 2003)
Published Online 22 years, 7 months ago (Jan. 15, 2003)
Published Print 22 years, 7 months ago (Feb. 1, 2003)
Funders 0

None

@article{Beloin_2003, title={An extended role for the nucleoid structuring protein H‐NS in the virulence gene regulatory cascade of Shigella flexneri}, volume={47}, ISSN={1365-2958}, url={http://dx.doi.org/10.1046/j.1365-2958.2003.03347.x}, DOI={10.1046/j.1365-2958.2003.03347.x}, number={3}, journal={Molecular Microbiology}, publisher={Wiley}, author={Beloin, Christophe and Dorman, Charles J.}, year={2003}, month=jan, pages={825–838} }